Diaphragm compressor is a special type of compressor that plays an important role in many fields with its unique structure and working principle.
1、 Structural composition of diaphragm compressor
The diaphragm compressor mainly consists of the following parts:
1.1 Driving mechanism
Usually powered by an electric motor or internal combustion engine, the power is transmitted to the crankshaft of the compressor through belt transmission, gear transmission, or direct connection. The function of the driving mechanism is to provide a stable power source for the compressor, ensuring that the compressor can operate normally.
For example, in some small diaphragm compressors, a single-phase motor may be used as the driving mechanism, while in large industrial diaphragm compressors, high-power three-phase motors or internal combustion engines may be used.
1.2 Crankshaft connecting rod mechanism
The crankshaft connecting rod mechanism is one of the core components of the diaphragm compressor. It consists of a crankshaft, connecting rod, crosshead, etc., which converts the rotational motion of the driving mechanism into the reciprocating linear motion of the piston. The rotation of the crankshaft drives the connecting rod to swing, thereby pushing the crosshead to make reciprocating motion in the slide.
For example, the design of crankshafts typically uses high-strength alloy steel materials that undergo precision machining and heat treatment to ensure they have sufficient strength and stiffness. The connecting rod is made of excellent forged steel material, and through accurate processing and assembly, it ensures reliable connection with the crankshaft and crosshead.
1.3 Piston and cylinder body
The piston is the component in direct contact with gas in a diaphragm compressor, which performs reciprocating motion inside the cylinder to achieve gas compression. The cylinder body is usually made of high-strength cast iron or cast steel material, which has good pressure resistance. Seals are used between the piston and cylinder to prevent gas leakage.
For example, the surface of the piston is usually treated with special treatments such as chrome plating, nickel plating, etc. to improve its wear resistance and corrosion resistance. The selection of sealing components is also crucial, usually using high-performance rubber or metal seals to ensure good sealing effect.
1.4 Diaphragm components
The diaphragm component is a key component of the diaphragm compressor, which isolates the compressed gas from the lubricating oil and drive mechanism, ensuring the purity of the compressed gas. Diaphragm components are usually composed of diaphragm sheets, diaphragm trays, diaphragm pressure plates, etc. Diaphragm sheets are generally made of high-strength metal or rubber materials, which have good elasticity and corrosion resistance.
For example, metal diaphragm plates are usually made of materials such as stainless steel and titanium alloy, and are processed through special techniques to have high strength and corrosion resistance. The rubber diaphragm is made of special synthetic rubber material, which has good elasticity and sealing properties. The diaphragm tray and diaphragm pressure plate are used to fix the diaphragm, ensuring that the diaphragm will not deform or break during operation.
1.5 Gas valve and cooling system
The gas valve is a component in a diaphragm compressor that controls the inflow and outflow of gas, and its performance directly affects the efficiency and reliability of the compressor. The air valve usually adopts automatic valve or forced valve, and is selected according to the working pressure and flow requirements of the compressor. The cooling system is used to reduce the heat generated by the compressor during operation, ensuring the normal operation of the compressor.
For example, automatic valves usually use spring or diaphragm as the valve core, which automatically opens and closes through changes in gas pressure. The forced valve needs to be controlled through external driving mechanisms, such as electromagnetic drive, pneumatic drive, etc. The cooling system can be either air-cooled or water-cooled, depending on the operating environment and requirements of the compressor.
2、 Working principle of diaphragm compressor
The working process of a diaphragm compressor can be divided into three stages: suction, compression, and exhaust:
2.1 Inhalation stage
When the piston moves to the right, the pressure inside the cylinder decreases, the intake valve opens, and external gas enters the cylinder body through the intake pipe. At this time, the diaphragm plate bends to the left under the action of the pressure inside the cylinder and the pressure in the diaphragm chamber, and the volume of the diaphragm chamber increases, forming a suction process.
For example, during the inhalation process, the opening and closing of the intake valve is controlled by the pressure difference inside and outside the cylinder block. When the pressure inside the cylinder is lower than the external pressure, the intake valve automatically opens and the external gas enters the cylinder body; When the pressure inside the cylinder is equal to the external pressure, the intake valve automatically closes and the suction process ends.
2.2 Compression stage
When the piston moves to the left, the pressure inside the cylinder gradually increases, the intake valve closes, and the exhaust valve remains closed. At this point, the diaphragm plate bends to the right under the pressure inside the cylinder, reducing the volume of the diaphragm chamber and compressing the gas. As the piston continues to move, the pressure inside the cylinder increases continuously until it reaches the set compression pressure.
For example, during compression, the bending deformation of the diaphragm is determined by the difference between the pressure inside the cylinder and the pressure in the diaphragm chamber. When the pressure inside the cylinder is higher than the pressure in the diaphragm chamber, the diaphragm plate bends to the right, compressing the gas; When the pressure inside the cylinder is equal to the pressure in the diaphragm chamber, the diaphragm is in equilibrium and the compression process ends.
3.3 Exhaust stage
When the pressure inside the cylinder reaches the set compression pressure, the exhaust valve opens and compressed gas is discharged from the cylinder through the exhaust pipe. At this point, the diaphragm plate bends to the left under the pressure inside the cylinder and the diaphragm chamber, increasing the volume of the diaphragm chamber and preparing for the next suction process.
For example, during the exhaust process, the opening and closing of the exhaust valve is controlled by the difference between the pressure inside the cylinder and the pressure in the exhaust pipe. When the pressure inside the cylinder is higher than the pressure in the exhaust pipe, the exhaust valve automatically opens and compressed gas is discharged from the cylinder body; When the pressure inside the cylinder is equal to the pressure in the exhaust pipe, the exhaust valve automatically closes and the exhaust process ends.
3、 Characteristics and Applications of Diaphragm Compressors
3.1 Characteristics
High purity of compressed gas: Due to the diaphragm separating the compressed gas from lubricating oil and the driving mechanism, the compressed gas is not contaminated by lubricating oil and impurities, resulting in high purity.
Good sealing: The diaphragm compressor adopts a special sealing structure, which can effectively prevent gas leakage, ensure compression efficiency and safety.
Smooth operation: During the working process of the diaphragm compressor, the movement speed of the piston is relatively low, and there is no direct contact between metal parts, so the operation is smooth and the noise is low.
Strong adaptability: Diaphragm compressors can adapt to various gas compression requirements, including high pressure, high purity, flammable and explosive special gases.
3.2 Application
Petrochemical industry: used to compress gases such as hydrogen, nitrogen, natural gas, etc., providing raw materials and power for chemical production.
Food and pharmaceutical industry: used to compress gases such as air and nitrogen, providing a clean gas environment for food processing and pharmaceutical production.
Electronic semiconductor industry: used to compress high-purity gases such as nitrogen, hydrogen, helium, etc., providing a high-purity gas environment for electronic chip manufacturing and semiconductor production.
In the field of scientific research experiments, it is used to compress various special gases and provide stable gas supply for scientific research experiments.
In short, diaphragm compressors play an important role in many fields due to their unique structure and working principle. Understanding the operating principle of diaphragm compressors can help to better use and maintain this equipment, improve its efficiency and reliability.
Post time: Sep-12-2024